Boardmaster 4K discs

[porchy]

Out of boredom ive been looking at reading/writing floppy discs for the 4K in a PC.
Ive had some success reading the disc using omniflop but nothing 100% useable yet. I also been trying to dump a disc using the kryoflux device but as of yet I do not know what profile the disc confirms to.
Anyone got any input they can give me in regards to this?

Ta

 

[trm]

Unfortunately I've never seen any information at all about people successfully reading the disks

I've got a few blank DDs now so am intending to have a fiddle, if only to see whether any of these drives still work but I need to find a PC floppy drive first.

Have you tried something like a 'dd' dump of the floppy and then loading it into a hex editor or running it through 'strings'? If you've got a dd dump you can upload I'd be interested in having a peek.

 

[porchy]

well using the omniflop program the dump is complete. For example, my disc only has macros paldump program on it.
The dump can be found here: http://www.jammarcade.net/files/Drive.img

Im not sure if its any recognised format and not completely certain how it allocates space but im sure some knowledgeable fella would be able to knock up a small program to read and write this. When I have some more spare time I might try writing some non basic info to the disc and trying again.

Its the only way I could think of to "upload" a program to the BM from PC

porchy2011-09-02 19:59:31

 

[trm]

Thanks for the image. Will have a look.

Are you interested in joining in with the firmware disassembly? I've got to shoot as I'm going out for dinner 10 minutes ago

but I'm looking into the hardware for the HPIB interface after Macro's suggestion about repurposing it for a USB interconnect, but maybe with a view to using plain HPIB to get data in/out of the BM4K initially.

 

[porchy]

sounds very interesting. not sure how useful id be but would gladly help whenever i can

enjoy you meal

 

[trm]

I'll PM you about the disassembly, but I should have checked first - do you do Z80 asm? Even if you only do it a bit you're probably better than me as I'm still learning programming patterns for Z80 asm having grown up with 'proper' assembly languages

As for the disk images, I've had a bit of a look and fortunately it looks relatively straightforward - so far.

On the image you uploaded was the disk formatted, paldump.bas saved on it once and then the dump created? I'm wondering whether there may be a deleted/overwritten file on there.

I've still not found a PC floppy so I can't create my own images. If it's not a major hassle and the disk wasn't formatted then had paldump saved on it without any other activity, would you mind doing that so we have the simplest image possible please?

cheers

tim

 

[porchy]

haha, i know essentially nothing about assembly. I can crawl my way through a MAME debug as long as ive got the internet at hand to help but i dont fully understand it all TBH.

The disk was formatted in the ABI and the paldump.bas file saved to it. The paldump.bas was already loaded into memory from a different disk.

I dont mind creating any other images you may need

 

[Macro]

well, format doesn't look too tricky.

has a 1 byte filler of 00, then 8/3 for the filename, then some numbers which presumably point to the start block of the file - nothing like a FAT table visible anywhere, possibly 16 bytes for each file information block

looks like it saved an 8k block for the paldump program, so maybe thats the size of each cluster. (8k is also set aside for catalogue as well)

a disk with several (different) files one would be good.

maybe
10 rem file 1

as file1.bas and so on, then the number sequence should be possible to resolve.

 

[porchy]

I'll get on it soon

 

[porchy]

ok, here is the second test file.
http://www.jammarcade.net/files/abi2.img